I think events like this are best understood as political theater, where an outraged element of the audience, large or small, is part of the speaker's props, script and performance. More often than not, we dutifully play our role to a tee, but in the speaker's drama.

If the proper creative energies were flowing, we would flip it around, and use the speaker's hate-speech as our prop in a counter-drama with a different conclusion. Make his or her hate rant a play-within-a-play, so to speak.

Otherwise, just don't go. Pass out a flyer outside to inform those who do attend, but don't join the cast.

And yes, I wouldn't put John Locke on a par with Ayn Rand, by any means. Locke's teachings on political and religious tolerance, though, are both problematic and instructive. He favored a breakthrough grassroots tolerance among Protestants, but didn't have much for 'Papists.'